2020/08/14 by Ankit Mahajan, Sandeep Sharma
Chemistry · Physics and Astronomy · #Advanced Chemical Physics Studies #Advanced Physical and Chemical Molecular Interactions #Dynamic Monte Carlo method #Formalism (music) #Hybrid Monte Carlo #Monte Carlo method #Monte Carlo method in statistical physics #Monte Carlo molecular modeling #Quantum Monte Carlo #Quantum, superfluid, helium dynamics #Scaling #Wave function #cond-mat.str-el #physics.chem-ph
paper · pdf · doi:10.1063/5.0025055
10 pages, 3 figures
arxiv created 2020/08/14 · openalex created_date 2020/08/21 · openalex publication_date 2020/11/18 · arxiv updated 2021/02/03 · openalex updated_date 2026/08/06
We present an algorithm for calculating the local energy of a multi-Slater wave function in orbital space quantum Monte Carlo (QMC). Recent developments in selected configuration interaction methods have led to increased interest in using multi-Slater trial wave functions in various QMC methods. For an ab initio Hamiltonian, our algorithm has a cost scaling of O(n5 + nc), as opposed to the O(n4nc) scaling of existing orbital space algorithms, where n is the system size and nc is the number of configurations in the wave function. We present our method using variational Monte Carlo calculations with the Jastrow multi-Slater wave function, although the formalism should be applicable for auxiliary field QMC. We apply it to polyacetylene and demonstrate the possibility of using a much larger number of configurations than possible using existing methods.